from datetime import datetime, timezone
from app.extensions import db
from werkzeug.security import generate_password_hash, check_password_hash


class User(db.Model):
    __tablename__ = 'users'

    id = db.Column(db.Integer, primary_key=True, autoincrement=True)
    username = db.Column(db.String(50), unique=True, nullable=False)
    password_hash = db.Column(db.String(255), nullable=False)
    name = db.Column(db.String(100), nullable=False)
    created_at = db.Column(db.DateTime, default=datetime.now(timezone.utc))
    updated_at = db.Column(db.DateTime, default=datetime.now(timezone.utc), onupdate=datetime.now(timezone.utc))

    def __repr__(self):
        return f'<User {self.username}>'

    def set_password(self, password):
        self.password_hash = generate_password_hash(password)

    def check_password(self, password):
        return check_password_hash(self.password_hash, password)

    @classmethod
    def create_user(cls, username, password, name):
        # Check if user already exists
        if cls.query.filter_by(username=username).first():
            raise ValueError("Username already exists")

        user = cls(
            username=username,
            name=name
        )
        user.set_password(password)

        try:
            db.session.add(user)
            db.session.commit()
        except Exception as e:
            db.session.rollback()
            raise ValueError(f"Error creating user: {str(e)}")

        return user

    @classmethod
    def get_user_by_username(cls, username):
        return cls.query.filter_by(username=username).first()

    def to_dict(self):
        return {
            'id': self.id,
            'username': self.username,
            'name': self.name,
            'created_at': self.created_at.isoformat() if self.created_at else None,
            'updated_at': self.updated_at.isoformat() if self.updated_at else None
        }